580HP Audi RS4 by Mcchip
 

Nice but pricey.

https://www.dpccars.com/blog/wp-cont...-4-700x325.jpg

From the article:
As you all might already know, the naturally aspirated FSI V8 is already nearing its maximum potential when it leaves the factory, so there isn’t much tuners can do to it.

Photos and article - 580HP Audi RS4 by Mcchip

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